This specification relates to rendering content items at ordinal positions in resources.
The Internet enables access to a wide variety of resources, e.g., web pages for particular subjects, search results pages from search engines, news articles, etc. Such access to content has also lead to the providing of additional content items with the content. For example, online advertising involves the providing of advertising content items with resources served over the Internet.
Many resources include environments in which the content items are displayed with the resource. These environments are generally referred to as content item slots. The slots are defined by code that is included with the resource code, such as instructions, scripts, etc. that execute when a browser is rendering the resource. The slots are typically individually identified by corresponding slot identifiers, and are assigned slot ordinal positions. When the resource is rendered, the user device also executes instructions that cause the user device to request content items, such as advertisements, to display in the slots. A content item server selects content items for the slots in response to the request and sends the selected content items to the user device. The content items also are ordered according to a ranking, and each content item has a respective ordinal position in the ranking. The content items are then rendered in the slots according to corresponding ordinal positions of the content items in the ranking and the slots. For example, the content item with the highest respective ordinal position relative to respective ordinal positions of other content items is rendered in the content item slot with the highest slot ordinal position with respect to the slot ordinal positions of other content item slots, and so on.
The content item ordinal positions of content items that are served can be determined in a variety of appropriate ways. One of the most common ways is by an auction process. A content item sponsor, such as an advertiser, specifies bids for placement of content items in resources. The bids are input to an auction process that takes into account the bids and other factors, such as historical performance of the content items, how well the content items match the content item request, etc. The auction process generates an auction score for each participating content item based on these factors. The content items are then ranked according to their auction scores, and the top ranked content items are selected and served in response to the request. Typically one content item is selected for each content item slot, and the respective ordinal positions of the content items correspond to the respective positions of the content item slots.
The slot ordinal positions for a resource can also be determined in a variety of appropriate ways. For example, the slots may be ordered according to the sequence by which they are rendered, such as a top slot being first in the ordinal positions and a bottom slot being last. Alternatively, the slots may be ordered according to a sequence that is independent of the rendering order. The sequence may be, for example, coded into the resource, or, alternatively, determined by the content item server based on historical performance of slot positions.
Typically the slot ordinal positions are such that a top-ranked content item is displayed in the viewport when the resource is rendered.